I'm a librarian who loves anime, manga, and reading a wide variety of genres.
I'm not fond of Woodbury's decision to use "wizard" and "wizardess" for the people Tokyopop generally called "sages."
I don't know which word is a more accurate translation, so I can only really speak to my preferences, and I prefer Tokyopop's "flying sage" and "grounded sage" more than Woodbury's "wizard of the air" and "wizard of the earth." Woodbury's choice of words implies powers that most of these people don't have. They're really just ordinary people granted immortality by being listed in a special registry. If they're "grounded sages"/"wizards of the earth," they live in the palace and have more direct political power than if they live away from the palace and are therefore "flying sages"/"wizards of the air."
Also, "sage" worked well for both men and women. "Wizardess" makes me grit my teeth. That said, I like that Woodbury went with emperor and empress for the rulers. Tokyopop's decision to use "king" regardless of the person's gender always seemed a bit odd to me.